Report of Chesapeake Biological Laboratory R. V

Report of Chesapeake Biological Laboratory, 1938

Item Type monograph

Authors Truitt, R.V.

Publisher Chesapeake Biological Laboratory

Download date 25/09/2021 23:20:49

Link to Item http://hdl.handle.net/1834/28746 REPORT OF CHESAPEAKE BIOLOGICAL LABORATORY 1938 R. V. TRUITT*

The program of work at the Chesapeake Biological Laboratory is being developed in a direction that will further the understanding of biological principles underlying conservation planning as well as to encourage the development of fundamental research. Efforts largely are centered in two directions, namely, research and teaching. Research problems are broad in their scope and many of them possess an important bearing on the preservation of natural resources in animal and plant life. Instructional work pertains to basic biology and to the status of natural resources as well as remedial measures that may assist in their development. Substantial progress was made in 1938 both in respect to additions made in the physical plant and to the problems effec- tively pursued by an energetic staff. The completion of a new and adequate building placed at the disposal of those working at Solmo- mons Island a greatly needed adjunct for the continuation of studies throughout the year. Much added equipment and space has been made available for the program being pursued, in the form of boats, technical apparatus, and added construction work for storage, Problems previously in course of study were continued during the current year, while new researches, in part economic and in part abstract, were initiated on Protozoa, on certain of the fin-fishes, and on new phases of the hydrography of the region. Certain of the previous investigations have been concluded.

ORGANIZATION Six educational institutions manifested interest and gave support to the work of the Laboratory: The Johns Hopkins Uni- versity, Western LVaryland College, Carnegie Institution of Wash-

* Dr. Truitt is, Director of the Chesapeake Biological Laboratory dn Solomons Island, Professor of Zoology in the University of Maryland, and Biologist, Mlaryland Conservation Commission. ington, Goucher College, Washington College, and University of Maryland. The administration of the Laboratory's program is vested in an executive committee composed of representatives from the aforementioned institutions.

Executive Committee : ROBERTF. DUEB, Conservation Com?nissioner, Chairman. DAVIDALLEN ROBERTSON,President, Gouclzer College. ISAIAH BOWMAN,President, Johtzs Hopkins University. H. CLIFTON BYRD, President, University of Maryland. FREDG. HOLLOWAY,President, Western Ma~ylandCollege. GILBERTWILCOX MEAD, President, Washington College. R. V. TRUITT,Director (ex-officio) .

The teaching and research programs of the Laboratory are administered by a Committee on Investigation and Instruction, the members of which are listed below, with the names of the institutions they represent. Committee on Investigation and Instruction: R. V. TRUITT,PH. D., University of Maryland, Chai~man. PAULS. CONGER,M. S., Curnegie Institution of Washington. GAIRDNERB. MOMENT,PH. D., Goucher College. S. 0. MAST, PH. D., Johns Hopkins University. JULIAND. CORRINGTON,PH. I)., Washington College. LLOYDM. BERTHOLF,PH. D., Western Maryland College.

Staff Members : The following named persons constituted the permanent staff of the Laboratory. A. A. BLAIR, PH. D., Assistant Fishery Biologist. A. G. LANG,PH. D., Associate Botanist. R. A. LITTLEFORD,PH. D., Associate Zoologist. J. H. MCLAIN, B. S., Assistant Chemist. HARVEYMISTER, Captain, In Charge of Boat. C. L. NEWCOMBE,PH. D., Ecologist, In Charge of Research. B. B. SHEPHERD,B. S., Research Assistant. R. V. TRUITT,PH. D., Biologist, Director, D. H. WALLACE,M. S. Assistant Fishery Biologist.

GENERAL PROGRAM Teaching : The teaching program of the Laboratory followed, in the main, the established alignment of courses. The subjects offered have been selected to provide the student with an opportunity - for mastering basic biology and to acquire facts essential for understanding and contributing to the problems of conservation. As in the past, courses in Economic Zoology, Invertebrate Zoolcgy, and Biological Problems were offered. Due to unavoidable cir- cumstances, it was necessary to remove temporarily from the curriculum the course in Diatoms and that in Algae. The introduc- tion of a new course of study, Protozoology, has helped greatly to strengthen the program of teaching. A list of the courses 2nd the instructors offering same is given here: , Economic Zoology-Marcus C. Old, Ph.D.-Ursinus College. Invertebrate Zooiogy-Henry Olsen, Ph.D.-Wilson Teachers

I College. Protozoolcgy-Richard Kudo, Ph.D.-University of Illinois. Experimental Zoology-Curtis L. Newcombe, Ph.D.-University of Maryland. Biological Problems-Staff.

Researches of a more fundamental as well as applied charac- ter have been in progress on several of the more important Bay forms, and on the environmental factors governing their distribution and abundance. Thus special aspects of the biology of the Rock, Roccus lineatus, the Shad, Alosa sapidissima, the Croak- er, Micropogon undulatus, the Blue Crab, Callinectes sapidus. the Boring Sponge, Cliona celata, the Oyster, Ostrea uirginica, the Sea Nettle, Dactylometra quinquecirrha, the Snail, Littorina irrorata, the Clam, Venus mercenaria, and other forms have been investigated. Qualitative and quantitative s~udiesof the microscopic animal and plant life in the Bay waters, throughout the different seasons, are being continued. Information has been gathered on certain local fish and oyster parasites. Also, much attention has been given to the areas of the Bay in which there is destruction of life due to pollution. Other unfavorable environments that have received attention are the low oxygen water-layers occurring mar the bottom over extensive areas of the Bay.

Fishes : ROCK OR STRIPED BASS. The program of investigation on the more important fishes was continued with the Rock, Roccus lineat us, and the Shad, Alosa sapidissirna, while added emphasis was given to the study of the Croaker, Micropogon undulatus, for which a detailed program of attack has been developed and initiated. To a limited extent both the Shad and the Croaker were tagged during the year. The return of tags, from some three thousand and five hundred Rock released in the fall of 1937, in Maryland, Virginia, and North Carolina, shows a marked decline as compared with like returns from fish tagged in 1936. Up to October 1, 1938, three hundred and thirty-five of the fish had been recaptured, that is, approximately ten per cent of the total number released. This decline in returns seems to indicate a lessened availability to the fisherman caused by the greatly reduced numbers of the fish of the 19 3 4 brood, which in 19 3 6 and 19 3 7 composed a "decidedly greater part of the catch. During the current year, very few recap- tures were reported from the fish released in 1936, no tags bzing returned during the last six months. This fact affords a strong indication that the method of tagging employed is not enti~ely satisfactory for experiments designed to yield data over a period of several years, although the results obtainsd have marked values for the first and even the second year after release, the period during which tags have been established to be durable, and the method employed efficient. Tagging operations during the 1937 season bear out previous findings concerning out-of-Bay movements, in that five marked Rock migrated to other bodies of water. Two of these fish passed to northern waters, while one, marked in the James River, was recaptured in Albemarle Sound, North Carolina. The latter represented the first recapture of fish marked in the Chesapeake Bay from a point south of that body of water. Two North Carolina tagged fish were recaptured in New England waters. Tagging within Chesapeake proper, during 193 7, indicated movements in the main schools of Rock corresponding to those observed from previous tagging. However, the striking winter migrations of 1936 and 1937, from the upper Bay to the James River, were not repeated. Rather, the fish tended to remain in the deeper areas in the upper reaches of the Bay. Further information was gained from tags as to the migration routes to spawning grounds which are located, typically, just above the brackish water areas in the Bay and its tributaries. Many hundreds of observations were made on gonad development in the Rock in order to determine more definitely the season of spawning and the size and age at the time of sexual development. The peak of the spawning season is found to be about May 1. Females mature at approximately eighteen inches in Iength and in their fourth year of age, whereas the males mature while younger and at smaller sizes. BUILT-IN EXPERIMENTAL TANKS

In order to determine the part the 1934 brood was playing in the catches of the various types of fishing gear, upward of five hundred measurements were made on Rock, which measurements afford data for the determination of the rate of growth as well. Tank experiments on food consumption and growth rate of this fish have been carried on since the summer of 1937. Fish hatched in 1937 have thriven under controlled conditions, and by Novem- ber, 1938, had reached an average length of eight and one-half inches, a size that compares most favorably with native fish in the open waters. These observations have demonstrated that the greatest quantity of food is consumed by the fish during Septem- ber and that the smallest quantity is consumed in January. Con- trolled feeding experiments apparently verify observations made on the winter food habits of this fish in nature in that food was consumed throughout the period of low temperatures. Collection and analysis of statistical data on the catches of Rock have been continued and expanded. Further analysis on pound net catches have corroborated the information derived from measurements of samples, in that they indicate a marked decline in the quantity of the 1934 brood. However, there has been a relative increase in the capture by haul seines indicating, possibly, that the larger fish, from four to eight pounds, may change their habitat and are, therefore, not as available to pound nets as was formerly the case.

SHAD. The 1937 program for Shad work was greatly expanded over the previous year in cooperation with the U. S. Bureau of Fisheries. Added tagging work was accompanied with racial and gonad studies on this fish, Approximately six hundred and twenty-five specimens were tagged during the spring run. Stomachs were collected from about four hundred fish for food analysis, Of the Shad tagged, three hundred and thirty were released during the early part of April, 1938, near the mouth of the Chesapeake Bay, of which approximately twenty-eight per cent were recaptured, the greater part being taken in the vicinity of actual tagging. In the head-waters of the Bay, especially at Conowingo Dam, further tagging operations were carried on during June. Two hundred and twenty-five fish were marked by external tags, such as previously used, and sixty-two additional fish were tagged with internal or belly tags, as well as with external markers. This experiment was designed to determine the fishing intensity as well as the number of spawners which return~d during the following seasons. Comparatively few of the tags released in this immediate experiment have been returned, possibly because the fish were released after the general fishing season had expired. One of these tags was later taken from New Jersey waters, giving further evidence of the fact that there is some northward migration after spawning of the Shad takes place in the Chesapeake area.

Shad racial studies were continued during the year on fish from New York and the Chesapeake Bay, in which there was gained further information indicating that distinct populations exist in the two areas. CROAKER. Tagging operations started on the Croaker in 1937 were continued during the 1938 season both at the mouth of the Bay and in Maryland waters. Of the several hundred tagged fish released, a sufficient number of returns has not been received to date to justify analysis. Length, weight, and scale samples have been collected from more than one thousand fish, while gonads have been examined for stages of development. The gonads show gradual ripening during the summer with well-developing roe and milt in September and October. These observations are to be continued during the winter season on the Atlantic Coast south to Cape Hatteras. It is anticipated that the observations being made will offer information on migration habitats, spawning areas, rate of growth along with the size and age of sexual maturity, conditions in the fishery, and added facts about the general biology of the species which is outstanding in Maryland, both commer- cially and in a sportative way, HERRING, Studies of both the Branch and the Glut Her- ring (Pornolobus pseudo-harengus and P. .aestivalis, respectively) in a structural way, have been furthered, though this phase of the fish program is still somewhat preliminary. Variations in the young have been found in widely separated areas as well as within definite river systems of the Chesapeake Bay, More inten- sive study of this problem is planned in which all of the important rivers are to be covered in an effort to determine the main source of the supply as well as to gain added general, biological information about these commercial forms.

Protozoa : A general survey of the free living Protozoa in the Chesa- peake Bay has been resumed and greatly extended, after a discon- tinuance of some years. This study aims to show what forms are most abundant during each season and to establish their relaticn- ships to the other forms in the Bay as well as to the physical and chemical conditions that characterize the different environments. Special attention is being given to the systematic aspects of this study in an effort to bring out the structural modifications that typify forms from the various areas. Currently, ninety-six brackish water and forty-five fresh water protozoans have been listed. Examinations of oyster tissues collected from the general region of Solomons Island for protozoan parasites yielded negative results. The parasites of the oyster which seems to be widely distributed in European and American coastal waters was not found to be of particular significance to oyster culture of the area studied, thus affording contrast to the situation reported in certain southern waters. In this connection, projected protozoan studies center around the myxosporidian and other protozoan fish parasites of the region. Hydrographic Studies: The hydrographic studies have been extended and intensified in such a way as to include a broad basis for analysing the biotic environment. The purpose of these studies is to find out the conditions operating in Chesapeake Bay waters that determine the kind and abundance of life present. Concerted effort is being devoted to the following problems: (1) the physical and chemical conditions in the water that modify existing life, (2) the pro- ductivity of the water, (3) the extent and degree of injury done by pollution in the local waters, (4) the extent and distribution of waters low in dissolved oxygen, the causes for their occurrence as well as their fluctuations, and (5) the plankton of the local waters with special reference to the efficiency of current quantitative methods of measurement. Studies on the physio-chemical conditions show that the surface bottom temperature variation rarely exceeds 3O C. The most conspicuous rise in water temperature occurs in April and May, while the corresponding decline takes place in October and November. A significant and consistent condition in the Bay lies in the stratification of the water with respect to salinity. This condition modifies the incidence of other major environment factors. The importance of the several river systems that flow into the bay on the waters of the Bay proper is very pronounced. They are responsible for the addition of large quantities of phos- phates, for example, to the Bay for use in plant and, subsequently, animal nutrition. The phosphate content of the Bay waters, in summer, commonly ranges as high as 0.33 x mg. -atoms of P per liter at the surface and 2 x mg. -atoms in the bottom waters. The Patuxent River waters, at the upper stations, contains an average concentration of about 0.95 x mg. -atoms of P per liter during the summer. Much lower values prevail in winter. The actual biological fertility of the Bay waters has been approached from an additional point of vicw, so-called "seeding on" experiments in progress which involve the recording of the types and quantities of organisms that become attached to submerged objects during the different seasons of the year. By means of counts and volumetric determinations made periodically, information is being assembled indicating the time of set, rate of growth, and degree of survival with respect to a variety of typical Bay forms. Pollution studies were centered in the Patapsco area and Curtis Bay. Information has been assembled pertaining to the kind and relative amounts of effluents in these areas. Their re- sultant effects on the water are being determined by chemical analyses. The degree of toxicity of the more important effluents is being tested for, in the laboratory, by using shrimp and fishes for experimental animals. By using drift bottles, it has been possible to throw some light on the prevailing water movements in respect to their action on the removal of pollutents as well as general current phenomena. A clearly defined oxygen stratification has been established to prevail over large areas of the Bay from about June the first to about October the first, with very low oxygen concentration in the bottom waters. This is accompanied by an equally pronounced salinity stratification of opposite gradient. At depths of eight to ten meters the oxygen concentration is frequently as low as 2cc per liter (35% total saturation), Below a depth of twelve meters, the concentration is usually under 1 cc per liter (1 6% saturated) and deep samples are often found to contain no measurable oxygen, Sometimes in summer the waters become well mixed; however, the stratified condition very quickly returns. As a result of these observations, studies are in progress which aim to show how important these so-called "oxygen deserts" are in the economy of the Bay. It has been demonstrated that certain bottom feeding fishes are exceedingly resistant to this low oxygen condition. Plankton studies are being continued with special reference to an evaluation of the food relationships that obtain.The methods employed in these studies have been the subject of considerable experimentation. Major attention is being given to Copepods, Protozoa, fish larvae, and Diatoms. The primary importance of Copepods in the aquatic food chains has prompted an investigation into the extent to which larval as well as adult Bay forms con- sume them. L,ocal as well as seasonal variations in the distribution and abundance of these important Crustacea are receiving attention. Concerted effort is being put forth to integrate these re- lated problems which within themselves constitute a firm basis for formulating scientific principles that may be applied to the whole field of marine conservation. WATER-SAMPLING EQUIPMENT

Mol lusca : Oyster, Ostrea uirginica, studies have been continued in an effort to establish added seed producing beds, and to determine on a practical basis the value of seed oysters produced upon them. The successful development of a seed bed upon a vastly depleted area located in the upper reaches of the Honga River has previously been reported. Seed taken from it and planted in five widely separated sections has been carried under observation for a full year and with marked success. The areas used, privately controlled grounds, are located in Pocomoke Sound, in the Patuxent River, in the Nanticoke River, and in the sea-side waters of Chincoteague Bay. A minimum of three hundred bushels of seed was used in every case. These oysters have not only survived but have thriven to a point of nearly doubling their dimensions. Final interpreta- tion of the results obtained will be delayed at least one more full year, though developments to date are exceedingly promising. Common mussels, Modiolus dirnlssus, have been unusually abundant on the oyster beds of Maryland during the fall season of 193 8. Their presence has been wide-spread and a very considerable annoyance to the watermen engaged in the oyster industry, in that they may completely cover oysters over and they are difficult to "cull" off or remove, This condition is reflected in the price of the catch. Mussels are symbiotic forms and are not hcld to affect oysters adversely. They occur infrequently in numbers sufficiently great to afford continuing observations. Growth studies of Chesapeake molluscs have long occupied an important place in the Bay studies. Work on the Oyster is now in progress which aims to contribute to existing information on the following points: (1) variation in body proportions and shell weights throughout life, (2) effect of crowding on the amount of shell produced, (3) the significance of food as a limiting factor in rate of growth, and (4) the importance of salinity in modifying the growth. These studies are being prose- cuted in conjunction with the "Cultch" experiments referred to above. Heretofore, there has not been available knowledge as to the cytological changes taking place in the gonads of the molluscs of the Bay during the different seasons of the year. Monthly collec- tions of the littoral Periwinkle, Littorina irrorata, have permitted careful cytological analyses throughout every month of the year. The results fail to reveal cytological evidence of changes in the gonads during the winter months. Maturation of the germ cells begins in the Spring, during April and May, and spawning actu- ally occurs during June and July. Following this period the gonads again become inactive. Maturation begins in this snail when it reaches 15mm. or more in length. The snails are definitely bisexual and there is no evidence of a change in sex in their development.

The Blue Crab: Studies involving the Crab, Callinectes sapidus, were son- tinued during the past summer. Tagging operations carried on during 19 3 5 and 19 3 6 along the coast from North Carolina to New Jersey, inclusive, and in the Chesapeake Bay produced only one tag, indicating, therefore, that the life span of the particular year class had been exhausted. No further tagging operations have been deemed necessary, since, with approximately eleven per cent tag returns, the desired information on crab migration and distribution, in the area under consideration, has been considered as established. Observations have been continued on the early developmental stages, a work supported in part by the Fisheries Commission of Virginia, and in which headquarters were established at Cape Henry, Virginia. This work was planned to the end of rearing through the various stages to maturity, it previously having been demonstrated that specimens can be reared from the late larval stage through the juvenile instars to the late moults. Many hundreds of observations were carried on in this connection without contributing greatly to previous experiments and information gained therefrom. The work clearly demonstrates that the hatching and rearing of the early stages of the crab is impossible in the waters of lower salinities in the upper reaches of the Bay, Casual observations over a period of years have indicated a high death rate among crabs used in both the soft crab and the hard crab branches of the crab industry. To determine the actual losses in the soft crab industry and to find out, if possible, through observation and experimentation, the underlying causes of the high mortality, as well as possible methods for the cor- recting of same, Crisfield, Maryland, was selected to become the center of this study, not only because of the vastness of its industry and the high death rate experienced there, but because of its many natural advantages, Typical purchase, sale, and mortality records were kept in cooperation with eight long-established soft crab dealers. Many hundreds of "peeler" crabs in varying degrees of maturity were marked and held on floats under conditions common to the sec- tion-crabs selected from the catches made by the different fishing methods such as "scrapes" and "trot-lines", and crabs taken from catches handled carelessly, with unnecessary exposure, for instance, as well as from well-handled catches. The program for this work is planned to the end that the effects of tide, sunlight, chemical changes in the water, overcrowding, and like factors operating on penned crabs may be determined. Shading, submergence, and greater circulation over the floats are to be experimented with as possible remedial measures. Data collected during the current year indicate that, while the hard crab lossage is much less than that of the soft crab, there is a very high death rate among crabs in the soft crab industry, which may exceed 50% of all crabs confined in floats, under certain conditions and at certain seasons of the year. This work has not progressed to a point that will permit of concrete recom- mendations for the correction of the conditions that obtain in the industry, but there are indications that the outstanding single factor operating to the destruction of penned crabs is found in the method employed in capturing and transporting the catch, in which there is undue out-of-water exposure. Growth studies of this crab were aimed to show the nature of certain characteristics such as size proportions, time required for moulting, conditions governing moulting, percentage increase during moulting, sex variations, and the number of moults. In these studies four linear dimensions were considered, namely, width, length, eye-to-spine dimension, and the length of the pro- podite of the right chela. It was found that length constitutes a better standard index of size than either of the other variables examined. There seems to be a consrant differential growth rate with respect to the four variables studied. At a width of about 140 mm., the theoretical average size ar: which sexual maturity is reached, a new relationship is established that remains fairly constant. Expansion is normally completed within six hours after the moulting process, the greater part being completed by the end of the first hour. Male crabs and immature females complete expansion more rapidly than the females that are in their last moult. Specimens 16 mm. in width increase about 11% during moulting, whereas those 104 mm. long increase about 39%. In males, the relationship between the initial and final sizes changes conspicuously at an initial width of 89 mm. This is considered to be the size at which sexual maturity occurs in the male crab. It has been estimated that the number of moults of male crabs above 20 mm. in width is eleven, being two more than the number for female specimens of the same initial size.

Boring Sponge : Life history studies on the Boring Sponge, Cliona celata, and the relation of this organism to oysters have been in progress for three years. During that period it has developed that at least two species of sponges are common to the Bay and its tributaries, both BORING SFONGE-INFESTED AND UNIFESTED OYSTERS of which follow the same general behavior pattern in their com- mensal relationships. Both species riddle shells whether on living oysters or otherwise. The general tunneling activities are similar and both types reproduce by gammulation as well as by sexual methods, concerning the study of both of which methods of reproduction considerable progress has been made. Further progress has been made with respect to the methods of and the mechan- ism for boring. Experimental procedure used in this study requires that the Iiving material be carried under both controlled conditions and in wire cages overboard approximating natural conditions. STREAM SURVEY Work previously initiated on stream surveys in certain bodies in Baltimore County were completed and reported separately during the past year. The immediate purpose of this work was to determine the fitness of the streams under consideration for fish life, with special reference to conservation practices in trout planting. New work was started in Montgomery County during June of this year, following the line of attack previously employed, as a result of which it has been recommended that in only two or three of the many streams should trout be used. In the. . streams recommended for development only large trout, legr:~- mate sizes for capture, should be released, since, because of several factors, including temperature, erosion, and food, these streams are not suited to propagation.

BIOLOGICAL SURVEY Valuable additions have been made to the check list of 50- logical forms in the Solomons Island Region. The fish collection has been greatly expanded and improved, while up-to-date storage and exhibit jars have been secured to hold it. Existing knowledge of the molluscan fauna of the Bay has been based largely on rm- dom samples taken by visiting collectors. To provide a more complete knowledge of the distribution and abundance of this fauna, systematic studies are being initiated which, it is hoped, will result in a complete collection of the representative mol!uscs of the region. In addition to valuable additions to the protozoan records for the region, a comprehensive outline has been prepared on the fresh as well as brackish water algae of the region.

EDUCATIONAL WORK

H The educational work of the Laboratory has included class instruction in biology for advanced undergraduate and graduate students, field explorational studies, evening seminars on current Bay problems, illustrated public lectures by visiting scientists on biological subjects of general interest, and, in addition, lectures by staff members on local conservation problems in biology given before numerous organizations throughout the State. Class instruction was given in Invertebrate Zoology, Eco- nomic Zoology, Protozoology, Experimental Biology, and Biolog- ical Problems, Present facilities have limited the class attendance to eight students, and the credits per course ranged from three to six credit hours for the six-week period of the summer teaching session, Graduate students were permitted to take research work during the entire summer. Registered students received credit through the cooperating institution of their choice. Field explorational studies included trips to particular places in the Bay for observational purposes, thus giving the student a first-hand acquaintance with the flora and fauna of the Bay as well as the conditions under which the sea food industries operate. The evening seminars are designed to acquaint the Laboratory personnel with the diverse research problems that are in progress. These lectures have been extended into a broader field of subject matter by the public lectures made possible through the kind cooperation of outstanding scientists from outside institutions. Mr. Gilbert Klingel, of the Maryland Natural History Society, gave an illustrated lecture on "Explorations On The Great Inagua Islands" and Dr. Samuel Williams of the University of Pittsburg presented a most informative lecture on "Amazon Travels". In response to numerous requests, staff members addressed many scientific organizations, schools and wildlife organizations, on the general subject of conservation. The successful filming of the story behind the development of the Blue Crab, the Oyster, and the Sea Nettle has played an important role in stimulating widespread interest as well as cooperation on the part of the public in attacking the many problems so much in need of elaboration.

STATE COMMISSIONS The facilities and contributions of the Laboratory have been placed at the disposal of the several agencies of the State dealing with the formulating of conservation policies, with the regulation, and with the industrial aspects of the commercial fisheries. Its personnel has continued cooperation with the State Planning Commission, The Maryland Development Bureau, and the Mary- land Outdoor Life Federation, with a member serving on the staff of each of the three agencies.

PHYSICAL DEVELOPMENT Outstanding in the new physical developments at the Labora- tory has been the acquisition of a thoroughly modern dormitory of brick construction, with facilities for approximately fifty workers. This building has available in its kitchen space and a dining room to accommodate the personnel. In the main laboratory building, special room has been constructed to house the fishery research, the capacity of which is three workers. Four new store rooms have been constructed on the third floor of the laboratory building to house special equipment. A new macadamized road has been constructed around the laboratory property with two lanes, similarly constructed, leading into the grounds. Approximately fifteen hundred square feet of concrete pavements have been laid. The grounds of the laboratory have been further graded and planted. A new boat, forty-seven feet in length and of twelve foot beam, pro- pelled by a one-hundred horse-power Gray motor, has been made available for work on the water, Many new facilities and much new equipment have been added during the year, including a constant temperature bath, refrigeration facilities, and a portable cooler, Nansen-Knudsen water bottles, aquaria, and an extension of reference works, etc.

PUBLICATIONS The library of the Laboratory has received numerous gifts during the year, including valuable monographs and reprints of current papers being issued by scientific institutions throughout the country. Publications representing studies of the Laboratory completed during the current year have been distributed to over five hundred institutions and workers in the field of marine biology. These reports are as follows: Populations of the Shad, Alosa sapidissima, Along the Western Atlantic Coast. Trans. Am. Fish Soc., Vol. 67, 1937, Vladykov, V. D. and Wallace, D. H. Is The Striped Bass, Roccus lineatus, of the Chesapeake Bay a Migra- tory Fish? Trans. Am. Fish Soc., Vol. 67, 1937 Vladykov, V. D. and Wallace, D. H. Annual Report for 1937, Chesapeake Biological Laboratory. State Press, December, 1937. Truitt, R. V. Variations in Growth Dimensional Ratios of the Hard Shelled Clam, Venus mercenaria L., Can. Jour. of Research, Vol. 16, Jan. 1938. Newcombe, C. L., Thompson, S. J., and Kessler, H. Notes on Maryland Algae. Bull. of the Torrey Botanical Club, 65: 293- 301, May, 1938. Bold, Harold C. Oxygen-Poor Waters of the Chesapeake Bay. Science, Vol. 88, No. 2273, July 22, 1938. Newcombe, C. L., and Horne, W. A. The 1938 Program of the Chesapeake Biological Laboratory. Collecting Net. Vol. 13, No. 8, Sept. 3, 1938. Newcornbe, C. L. The Relative Growth of Parts in the Blue Crab, Callinectes sapidus Rathbun. Growth, Vol. 2, No. 3, 1938. Gray, E. H. and Newcornbe, C. L. Studies of Moulting in the Blue Crab, Callinectes sapidus Rathbun. Growth, Vol. 3, 1938. Gray, E. H. and Newcombe, C. L. Status of Fishery Research and Chesapeake Bay. Trans. Am. Fish. Soc. (In press.) Truitt, R. V. and Wallace, D. H. Sport Fishing in Maryland, Weant Press, 1938. Truitt, R. V.

ACKNOWLEDGEMENTS The Laboratory has been most fortunate in having rhe cooperation not only of affiliated institutions but also of those that, through the bonds of common interests, are anxious to further the Chesapeake Bay studies in progress. Grateful thanks are extended to all those persons and institutions whose willing- ness to share in the wcrk has contributed so much toward its success.

Through the support of Johns Hopkins University, Dr. M. C. Old, of Ursinus College, continued his researches on the Boring Sponge while offering course work in Economic Zoology. Professor S. 0. Mast, of the Johns Hopkins University, served on the Laboratory's committee on investigation and instruction, while Dr. R. B. Roulson, of the same institution, offered fine cooperation in the development of the Laboratory's teaching program. Dr. Gairdner Moment of Goucher College served on the committee in charge of teaching and research. Washington College was again represented by Dr. J. D. Corrington, who, though unable to be in residence during the summer, proved very heplful in respect to committee assignments. Dr. Lloyd M. Bert- holf represented Western Maryland College on certain committees and offered helpful suggestions with respect to the Laboratory's program. The Carnegie Institution of Washington continued cooperation in the program. Mr. Paul Conger, its Research Asso- ciate, though unable to be present during the summer, served on the Committee on Investigation and furthered the studies of the diatom flora of the Chesapeake region.

Acknowledgement is made to various independent investiga- tors who gave much of their time and effort to the advancement of knowledge on some important line of study: Miss Ellen H. Gray, Mr. G. Francis Beaven, and Mr. Roy Robertson, biology teachers in the high schools of Maryland, who were engaged in studies on the Blue Crab; Professor Richard Kudo and Mr. C. L. Kanatzar, both of the University of Illinois, for their contributions in the field of planktonology; Dr. Henry Olsen, Wilson Teachers' College, for the active part he played in the teaching program; Mr. Fred McNall, of Cornell University, for his assistance in chemical studies; Miss J. Frances Allen, of Radford Col- lege, who succeeded in preparing a comprehensive list of local molluscs; Mr. George Butterfield, of Ironwood Junior College, who continued his cytological studies; and Dr. J. B. S. Norton, University of Maryland, and Mrs. Gladys Mitchell Lang, through whose efforts a comprehensive list of flowering plants in the vicinity of Solomons Island has been prepared. A number of institutions and individuals have cooperated to provide scientific apparatus necessary for the continuation of certain features of the program. In this connection acknowledgement is made to Captain Paul Whitney, Acting Director, U. S. Coast and Geodetic Survey, who very kindly loaned field equipment and installed permanent tidal gages from the Laboratory pier ; Mr. R. A. Nesbit, In Charge of Middle and South Atlantic Fish- ery Investigation, U. S. Bureau of Fisheries, who offered helpful suggestions and provided certain equipment pertaining to fishery researches; Dr. V. D. Vladykov, who during the preceding two years on leave of absence from the Biological Board of Canada assumed immediate direction of the fishery investigations, and who completed his work on the Chesapeake early in the year, after rendering a fine contribution to the knowledge of fish life in the Bay; Mr. M. C. Armstrong, of Hampton, Virginia, who has made available space and equipment aboard a modern trawler for coastal fish studies; and to Mr. R. A. Blunt, of the Buck Glass Company, Baltimore, who moulded a special drift bottle carrying markings and identification necessary for speedy returns, nearly three thousand of which were contributed to the work on current studies. Chairman Walter G. Mapp and the Commission of Fisheries of Virginia supported certain phases of the crab research at Cape Henry. The Laboratory is most appreciative of the interest in its work show by the American Philosophical Society, which institution has provided a research grant for the prosecution of the special low-oxygen problem now being investigated. The Maryland Conservation Department has rendered valued assistance and cooperation during the year. Appropriate boats, well manned, have been made available for field work, laboratory, and class routine. This Department, in full cooperation, efficiently handled the fiscal affairs of the Laboratory, negotiated all pur- chases, and offered continuous services toward the prosecution of the Laboratory's program of work.